9/11/2016 12:10 AM PDT

The IRS Demands a Couple Mil from Nelly

Uncle Sam nailed Nelly with a $2,412,283 federal tax lien in August. The tab is so big, the IRS could start seizing his assets and property.

He's also got state tax trouble -- earlier this year, the Missouri Department of Revenue said the St. Louis rapper owed $149,511 in unpaid state taxes from 2013. He originally owed a mere $113,533 ... but interest is a bitch.

Sources close to Nelly tell us he's already working with the tax authorities to resolve the issues.